Vacuum breaker



June 12, 1934. G g ass 1,962,381

VACUUM BREAKER Filed Dec. 15, 1952 2 Sheets-Sheet 1 IN VENTOR ffaefi A. 3/995.

A TTORNE VJ.

G. A. BIGGS VACUUM BREAKER June 12, 1934.

Filed Dec. 15, 1952 2 Sheets-Sheet 2 A TTORNE K7 Patented June 12, 1934 VACUUM BREAKER George A. Biggs, Springfield, Ohio, assignor to The James Leffel & Company, Springfield, Ohio, a corporation of Ohio Application December 15, 1932, Serial No. 647,349

2 Claims. (01. 253-117) This invention relates to improvements in vacuum breakers, and is adapted to be used in connection with various forms of turbines, particularly hydroelectric plants where there is more than one unit, or where a unit is synchronized with and supplies current in a transmission system in connection with other units.

In cases of this kind it sometimes becomes desirable to operate the unit as a synchronous condenser and then the turbine gates are closed and the generator and the turbine continue to rotate, the generator running as a motor, taking the necessary current from the other units, or the line to which it is connected. When operat- 5 ed in this mann r it becomes necessary to exhaust the water from the draft tube and the gate case of the turbine of the unit, which is operating as a motor, so that the turbine runner will not churn the water in the turbine gate 0 case.

The present vacuum breaker is intended to admit air to the draft tube or gate case at the proper moment automatically, and to close automatically when the vacuum has been destroyed, so as to prevent the water from the tail race coming back through the valve into the power house, in the event of a rise in the tail race water level, such as from flood and the like.

These and other advantages will appear from the following description taken in connection with the drawings.

Referring to the drawings:

Figure 1 is a vertical section through a turbine, showing applicants vacuum breaker attached thereto.

Figure 2 is a vertical section through one form of applicants vacuum breaker.

Figure 3 is a vertical section through a modilied form of breaker.

The vacuum breaker, the subject of the present invention, is adapted to be used with various forms of turbines and water-driven machin cry, and especially is adapted to be used in connection with hydroelectric plants, and for that purpose is attached either to the runner tube or to the gate case or inclosure. In Figure 1 it is shown attached to the gate case or inclosure A by means of a pipe 1, on top of which is located a housing 2. This housing has supported on top of it a casing 3 by means of screws 4.

Between the housing and the casing is a rubber composition seat member 5, held in position by means of the housing and the casing. This seat member is annular in shape and is adapted to cooperate with the valve in forming a close air and water-tight lit. The casing has a plurality of air slots 6. Located within the casing 3 and below the slots 6 is a spider 7, which has in the central part thereof a bearing 8. In line with this bearing 8 is a second bearing 9 formed in the upper end of the casing 3 for supporting a vertically disposed shaft 19, which has on its lower end a valve 11 adapted to engage the seat 5 for closing the passageway from the housing to the casing.

This valve is held on the lower end of the shaft 10 by means of a nut 12. To the upper end of the shaft 10 is attached one end of a lever 13 by means of a pivot pin 14. This lever is supported intermediate its ends by means of a link or pair of links 15, pivoted at one end by means of a pin 16 to a bracket 17 on one side of the casing 3. The other end or ends of the link or links 15 is pivoted by means of a pin 18 to the lever 13 intermediate its ends.

In the lever 13, beyond the pivot 18 from the pin 14, is a plurality of holes 19. These holes are used for supporting at adjusted points along the end of the lever 13, a weight 20 which has extending through its upper end a pin 21 adapted to fit through any one of the holes 19.

Located on one side of the casing is a shaft 22 supported by means of a bracket 23. EX- tending from the shaft 22 and rigid therewith is an arm 24, which has attached to its free end one end of a link section 25 by means of a pivot pin 26. Another section 27 or part of the connecting link is attached to the section 25 by means of a connection or turnbuckle 28 so that the full length of this link, composed of parts 25, 27 and the turnbuckle 28, may be adjusted by means of the connection or turnbuckle 28.

The free end of the section 27 is pivotally attached at 29 to one end of an extension 30 of the lever 13. By this means the lever 13 may be operated independently of the weight by the rotation of the shaft 22 in any suitable manner, or by any suitable means.

In the form shown in Figure 3 there is located on top of the casing 3 a housing 31, which incloses the upper end of the shaft 10. Around this shaft and resting upon the upper end of the bearing part 9 of the casing 3 is a spring 32, which has on its upper end a disc 33 adjustably supported on the upper end of the shaft 10 by means of a nut 3*1. This spring, acting upon the disc 33, tends to keep the valve 11 seated against the annular seat 5. In order to provide for the free escape of air from and the admission of air to the housing 31 there is provided an air hole 35.

In this form there is provided a shaft 22, which has extending therefrom an arm 24. In this form this arm 24 extends upwardly. However, it may extend in any convenient direction. Extending from the shaft 22 and rigidly attached thereto is a second arm 36, which extends into the casing 3 and has in one end thereof a slot 37 which receives a pin 38, suitably supported by the shaft 10. By this means the rotation of the shaft 22 will cause the arm 36 to move up and down, and through the slot and the pin move the shaft 10.

In the form shown in Figure 3 the valve closes automatically, due to the action of the spring 32, whereas in the form shown in Figure 2 the valve closes automatically, due to the action of the weight. The efiect of the weight upon the valve may be adjusted by means of the holes 19.

In the event that the gates are closed the water in the gate case escaping therefrom tends to produce a vacuum, and in order to relieve this vacuum applicants vacuum breaker is attached either to the gate case or to the runner tube. The suction upon the valve tends to open the valve and admits air through the housing 2 into the gate case or runner tube.

: again produced, when the valve will again automatically open for relieving the vacuum condition. The valve may be operated mechanically or manually by means of the shaft 22.

It will be understood that it is desired to cornprehend within this invention such modifications as come within the scope of the claims and the invention.

Having thus fully described the invention, what is claimed as new and desired to be secured by Letters Patent, is:

1. In a vacuum breaker, in combination with a gate case, a hollow body member forming a passageway into the case, an annular elastic seat on the body member around the passageway, a slotted casing attached to the body memher on the seat, a valve adapted to engage the seat and close the passageway, a stem on the valve guided by the casing, a lever pivoted at one end to the stem, 2. link pivoted at one end to the casing and pivoted at its other end to the lever intermediate its ends, and a Weight adjustably mounted on the other end of the lever tending to hold the valve on the seat.

2. In a vacuum breaker, in combination with a gate case, a hollow body member forming a passageway into the case, an annular elastic seat on the body member around the passageway, a slotted casing attached to the body member on the seat, a valve adapted to engage the seat and close the passageway, a stem on the valve guided by the casing, a lever pivoted at one end to the stem, a link pivoted at one end to the casing and pivoted at its other end to the lever intermediate its ends, a weight adjustably mounted on the other end of the lever tending to hold the valve on the seat, and mechanical means to unseat the valve and open the passageway.

GEORGE A. BIGGS. 

